Toners containing polyhedral oligomeric silsesquioxanes

Abstract

Disclosed is a toner composition comprising toner particles which comprise (a) a resin having chemically bonded thereto a polyhedral oligomeric silsesquioxane, (b) and an optional colorant.

1. A toner composition comprising toner particles which comprise (a) a resin having chemically bonded thereto a polyhedral oligomeric silsesquioxane, (b) and an optional colorant. 
     
     
       2. A toner composition according to  claim 1  wherein the resin comprises a polyester. 
     
     
       3. A toner composition according to  claim 1  wherein the resin comprises at least one amorphous resin and at least one crystalline resin. 
     
     
       4. A toner composition according to  claim 3  wherein the amorphous resin is of the formula 
       
         
           
           
               
               
           
         
       
       wherein m is from about 5 to about 1000. 
     
     
       5. A toner composition according to  claim 3  wherein the amorphous resin is the polycondensation product of the following diacids: 
       
         
           
           
               
               
           
         
       
       and the following diols: 
       
         
           
           
               
               
           
         
       
     
     
       6. A toner composition according to  claim 3  wherein the crystalline resin is of the formula 
       
         
           
           
               
               
           
         
       
       wherein b is from about 5 to about 2000 and d is from about 5 to about 2000. 
     
     
       7. A toner composition according to  claim 3  wherein the crystalline resin is of the formula 
       
         
           
           
               
               
           
         
       
       wherein n represents the number of repeat monomer units. 
     
     
       8. A toner composition according to  claim 1  wherein the resin comprises a styrene acrylate, a styrene butadiene, a styrene methacrylate, or a combination thereof. 
     
     
       9. A toner composition according to  claim 1  wherein the polyhedral oligomeric silsesquioxane is present on at least the surfaces of said toner particles. 
     
     
       10. A toner composition according to  claim 1  having a core-shell structure. 
     
     
       11. A toner composition according to  claim 1  wherein the toner is prepared by an emulsion aggregation process. 
     
     
       12. A toner composition according to  claim 1  wherein the polyhedral oligomeric silsesquioxane compound is present in the toner in an amount of at least about 0.5 percent by weight. 
     
     
       13. A toner composition according to  claim 1  wherein the polyhedral oligomeric silsesquioxane compound is present in the toner in an amount of no more than about 20 percent by weight. 
     
     
       14. A toner composition according to  claim 1  wherein the resin is reacted with a polyhedral oligomeric silsesquioxane compound which is 
       
         
           
           
               
               
           
         
       
       wherein R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , and R 8  are all cyclopentyl, 
       
         
           
           
               
               
           
         
       
       wherein R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , and R 8  are all isobutyl, 
       
         
           
           
               
               
           
         
       
       wherein R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , and R 8  are all isobutyl, 
       
         
           
           
               
               
           
         
       
       wherein R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , and R 8  are all phenyl, 
       
         
           
           
               
               
           
         
       
       wherein R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , and R 8  are all cyclohexyl, 
       
         
           
           
               
               
           
         
       
       wherein R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , and R 8  are all isobutyl, 
       
         
           
           
               
               
           
         
       
       wherein R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , and R 8  are all isobutyl, or mixtures thereof. 
     
     
       15. A toner composition according to  claim 1  further containing a charge control agent. 
     
     
       16. A toner composition according to  claim 1  wherein the toner particles have a volume average particle diameter of at least about 3 microns. 
     
     
       17. A toner composition according to  claim 1  wherein the toner particles have a volume average particle diameter of no more than about 20 microns. 
     
     
       18. A toner composition according to  claim 1  wherein the toner particles have a particle size distribution of GSD equal to no more than about 1.55. 
     
     
       19. A toner composition according to  claim 1  containing a pigment colorant. 
     
     
       20. A toner composition according to  claim 1  wherein the polyhedral oligomeric silsesquioxane compound is of the formula (RSiO 1.5 ) n  wherein n is 6, 8, 10, or 12, each R group, independently of the others, can be the same as the others or different from the others, and each R group, independently of the others, is (a) an alkyl group, including linear, branched, saturated, unsaturated, cyclic, acyclic, substituted, and unsubstituted alkyl groups, and wherein hetero atoms either may or may not be present in the alkyl group, (b) an aryl group, including substituted and unsubstituted aryl groups, and wherein hetero atoms either may or may not be present in the aryl group, (c) an arylalkyl group, including unsubstituted and substituted arylalkyl groups, wherein the alkyl portion of the arylalkyl group can be linear, branched, saturated, unsaturated, cyclic, and/or acyclic, and wherein hetero atoms either may or may not be present in either or both of the alkyl portion and the aryl portion of the arylalkyl group, (d) an alkylaryl group, including unsubstituted and substituted alkylaryl groups, wherein the alkyl portion of the alkylaryl group can be linear, branched, saturated, unsaturated, cyclic, and/or acyclic, and wherein hetero atoms either may or may not be present in either or both of the alkyl portion and the aryl portion of the alkylaryl group, (e) a siloxyl group, including linear, branched, cyclic, acyclic, substituted, and unsubstituted, siloxyl groups, and wherein hetero atoms either may or may not be present, (f) silyl groups, including linear, branched, cyclic, acyclic, substituted, and unsubstituted, silyl groups, and wherein hetero atoms either may or may not be present, (g) silane groups, including linear, branched, cyclic, acyclic, substituted, and unsubstituted, silane groups, and wherein hetero atoms either may or may not be present, or (h) a functional group selected from hydroxyl, amine, carboxylic acid, epoxide, fluoroalkyl, halide, imide, acrylate, methacrylate, nitrile, sulfonate, thiol, silanol, and combinations thereof, wherein two or more R groups can be joined together to form a ring. 
     
     
       21. A toner composition according to  claim 1  wherein the polyhedral oligomeric silsesquioxane compound is of the formula 
       
         
           
           
               
               
           
         
       
       or mixtures thereof, wherein R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , R 8 , R a , R b , and R c  each, independently of the others are (a) an alkyl group, including linear, branched, saturated, unsaturated, cyclic, acyclic, substituted, and unsubstituted alkyl groups, and wherein hetero atoms either may or may not be present in the alkyl group, (b) an aryl group, including substituted and unsubstituted aryl groups, and wherein hetero atoms either may or may not be present in the aryl group, (c) an arylalkyl group, including unsubstituted and substituted arylalkyl groups, wherein the alkyl portion of the arylalkyl group can be linear, branched, saturated, unsaturated, cyclic, and/or acyclic, and wherein hetero atoms either may or may not be present in either or both of the alkyl portion and the aryl portion of the arylalkyl group, (d) an alkylaryl group, including unsubstituted and substituted alkylaryl groups, wherein the alkyl portion of the alkylaryl group can be linear, branched, saturated, unsaturated, cyclic, and/or acyclic, and wherein hetero atoms either may or may not be present in either or both of the alkyl portion and the aryl portion of the alkylaryl group, (e) a siloxyl group, including linear, branched, cyclic, acyclic, substituted, and unsubstituted, siloxyl groups, and wherein hetero atoms either may or may not be present, (f) silyl groups, including linear, branched, cyclic, acyclic, substituted, and unsubstituted, silyl groups, and wherein hetero atoms either may or may not be present, (g) silane groups, including linear, branched, cyclic, acyclic, substituted, and unsubstituted, silane groups, and wherein hetero atoms either may or may not be present, or (h) a functional group selected from hydroxyl, amine, carboxylic acid, epoxide, fluoroalkyl, halide, imide, acrylate, methacrylate, nitrile, sulfonate, thiol, silanol, oxide, and combinations thereof, and wherein R a , R b , and R c  each, independently of the others, can also be imine groups, ammonium groups, cyano groups, pyridine groups, pyridinium groups, sulfate groups, sulfonate groups, sulfonic acid groups, sulfide groups, sulfoxide groups, phosphine groups, phosphonium groups, phosphate groups, nitrile groups, mercapto groups, nitro groups, nitroso groups, sulfone groups, azide groups, azo groups, cyanato groups, isocyanato groups, thiocyanato groups, isothiocyanato groups, urethane groups, urea groups, or combinations thereof, wherein two or more R groups can be joined together to form a ring. 
     
     
       22. A toner composition according to  claim 21  wherein at least one of R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , R 8 , R a , R b , and R c  is selected from methyl, O—N(CH 3 ) 4   + , ethyl, dibromoethyl, norbornenylethyl, vinyl, trifluoropropyl, chloropropyl, cyanopropyl, mercaptopropyl, aminopropyl, N-methylaminopropyl, propylammonium halide, allyl, polyethyleneoxy, isobutyl, cyclopentyl, cyclohexyl, isooctyl, 1-ethyl-3,4-cyclohexanediol, 3-hydroxy-3-methylbutyldimethylsiloxyl, aminoethylaminopropyl, phenyl, chlorobenzyl, chlorobenzylethyl, aminophenyl, N-phenylaminopropyl, trimethylsiloxyl, norbornenyl, —OSi(CH 3 ) 2 H, —H, —OH, 
       
         
           
           
               
               
           
         
       
       or combinations thereof. 
     
     
       23. A developer composition comprising (1) a toner composition comprising toner particles which comprise (a) a resin having chemically bonded thereto a polyhedral oligomeric silsesquioxane, (b) and an optional colorant; and (2) carrier particles. 
     
     
       24. A developer composition according to  claim 22  wherein the toner particles are present in the developer in an amount of at least about 1 percent by weight. 
     
     
       25. A developer composition according to  claim 23  wherein the toner particles are present in the developer in an amount of no more than about 25 percent by weight. 
     
     
       26. A process for preparing toner particles which comprises (a) contacting at least one resin and at least one POSS compound having a functional group capable of covalently bonding to the resin in an emulsion; (b) contacting the emulsion with an optional colorant dispersion, an optional wax, and an optional coagulant to form a mixture; (c) aggregating small particles in the mixture to form a plurality of larger aggregates; and (d) coalescing the larger aggregates to form toner particles, wherein the POSS compound reacts with the resin to become covalently bonded thereto during the process. 
     
     
       27. A process for preparing toner particles which comprises (a) contacting at least one resin in an emulsion; (b) contacting the emulsion with an optional colorant dispersion, an optional wax, and an optional coagulant to form a mixture; (c) aggregating small particles in the mixture to form a plurality of larger aggregates; (d) forming a second emulsion by contacting at least one shell resin and at least one POSS compound having a functional group capable of covalently bonding to the shell resin in the emulsion; (e) contacting the larger aggregates with the second emulsion to form a shell over the larger aggregates; and (f) coalescing the larger aggregates to form toner particles, wherein the POSS compound reacts with the resin to become covalently bonded thereto during the process.